What referendums have been related to education in Colorado in recent years?

Referendum C passed in 2005 is one of the most recent referendums involving education in Colorado in recent years. This referendum allows the state of Colorado to keep more of the tax money that was originally returned to the citizens due to the TABOR tax reforms that were passed in 1995. These TABOR tax laws say that the state of Colorado can only keep a certain amount of money from taxes based on the inflation and increase in population, but it short changes many of the necessary spending that Colorado once used this money on. Referendum C allowed Colorado to keep more money, and to spend more of this money on the public schools systems. The same ones that were lacking funds under the TABOR laws.

What interest groups are there related to education?

Here is a list of educational interest groups:
American Federation of Teachers
Center for Education Reform (Conservative)
Educational Excellence Network (Conservative)
Educational Resources Information Center (Government Resource)
EdWeb (Liberal Index)
National Education Association (Teachers' Union)
Partnership for Public Education (Liberal)
SchoolReport.com (Conservative)
Separation of School & State Alliance (Libertarian)

What does each group want changed or unchanged? What tactics are used to get reform?

The general goal of the majority of these interest groups is to increase the amount of funding to schools. They believe that schools need more money to better educate our youth, because after all they are the future leaders of our nation.

Which of these groups has been most successful in causing reform?

The American Federation of Teachers has been most successful in causing reforms because they are unified under their mission, “to improve the lives of our members and their families, to give voice to their legitimate professional, economic and social aspirations, to strengthen the institutions in which we work, to improve the quality of the services we provide, to bring together all members to assist and support one another and to promote democracy, human rights and freedom in our union, in our nation and throughout the world.” (http://usgovinfo.about.com/gi/dynamic/offsite.htm?site=http://www.aft.org/). They lobby in Washington D.C. to senators, and are the experts when it comes to education. They lobby to start legislation, and are extremely interested in improving education in America.